An Italian Army soldier gesture next to the barracks building which was destroyed by a car bomb, at the headquarters of Italy's paramilitary police in Nasiriyah, Wednesday, Nov. 12, 2003. At least 17 Italian soldiers and eight Iraqi civilians died. (AP Photo/Anja Niedringhaus)

Photo: ANJA NIEDRINGHAUS

An Italian Army soldier gesture next to the barracks building which...

2003-11-13 04:00:00 PDT Nasiriya, Iraq -- A suicide truck bomb exploded outside an international military police base here Wednesday, tearing off the facade of the three-story building and killing at least 26 people, including 12 Italian military police and a 10- day-old Iraqi baby.

The bombing, in which at least 100 more people were injured, was the deadliest attack to date on international troops who have come to Iraq at the request of President Bush to aid in U.S.-led reconstruction efforts. It was also the Italian military's single biggest loss of life since World War II.

Witnesses said at least one of the attackers had fired at the police with an assault rifle as the tanker truck approached the building. The police returned fire but were unable to halt the vehicle.

As the truck reached the facility, there was a huge explosion that sent a fireball into the air and blasted gaping holes in nearby houses.

Five young Iraqi women who were students at a local teachers college were burned to death when their car was incinerated. At least 18 Italian citizens, including the police and four soldiers, died. The infant who was killed was in its mother's arms in a nearby house when the explosion occurred. One of the mother's arms was amputated by the blast.

Coalition authorities said they did not know who had carried out the attack, but it bore the stamp of Islamic extremists, possibly linked to al Qaeda, who officials believe are behind a wave of high-profile suicide bombings in Iraq during the past three months.

Since the fall of Saddam Hussein, the Nasiriya area south of Baghdad has been one of the most peaceful regions of Iraq. Policed by Italians, Romanians, South Koreans and Iraqis, there has been little hostility toward foreign troops, and security has been more lax than in Baghdad, where most suicide bombings have taken place.

At the White House, President Bush mourned the Italian casualties. "Today in Iraq, a member of NATO, Italy, lost some proud sons in the service of freedom and peace," Bush said. "We appreciate their sacrifices."

In Italy, where some opposition parties have demanded an end to the country's involvement in Iraq, Prime Minister Silvio Berlusconi pledged that his government would not withdraw its 2,300 troops. "No intimidation will budge us from our willingness to help that country rise up again and rebuild itself with self-government, security and freedom," he told the Senate in an address broadcast nationwide.

The Nasiriya attack could prompt some countries that were considering sending troops to reevaluate their decision.

One hundred Portuguese soldiers who are supposed to arrive in the next few days may not arrive as scheduled, one coalition official said. And early today, Japan said it was considering postponing its first dispatch of troops until sometime next year instead of by the end of 2003.

The result of the damage in Nasiriya was reminiscent of the 1995 bombing of the Alfred P. Murrah Federal Building in Oklahoma City. The front facade of the building and part of the side were stripped off, leaving the rooms exposed.

The explosion occurred at about 10:40 a.m., when the streets of the city were full of people. It shattered windows at a courthouse more than half a mile away, sending shards flying that cut people who were attending a court hearing, said a lawyer who gave his name only as Abbas.

"How can you prevent these things from happening?" said the attorney as he sought treatment for his lacerations. "We just have to establish an Iraqi government."

The blast killed 12 Italian carabinieri, members of an elite military unit chosen to police the city. Four Italian soldiers, an Italian aid worker and an Italian filmmaker who was making a documentary about the deployment in Iraq were also among the dead. Another 20 Italians were injured.

Many of the carabinieri were among the first of their unit to have arrived in Iraq four months ago and were scheduled to leave in a few days, officials said. The Italians apparently were well liked on the streets of Nasiriya and were not perceived as being as tough as American troops in maintaining order.

The ease with which the tanker truck was able to reach the building called into question the security measures being followed.

The base, one of two used by the foreign police here, provided offices and housing for more than 200 carabinieri. It was not protected by the type of concrete barriers that have become common in Baghdad, where most car bombings have taken place.

Andrea Angeli, a spokesman for the U.S.-led coalition, said the international police in Nasiriya had not fortified the base because they wanted to be accessible to the public.

"The policy is to be open, to have a dialogue, to have contact with the people," he said. "This is a tragedy for the international community, and this is a big blow, really, for Nasiriya."

Cars approaching the base were required to drive around barriers designed to slow oncoming traffic, but the tanker truck was apparently able to negotiate these without a problem.

Some witnesses said that a second vehicle might have joined the attack, leading the way past the barriers.

There were several other armed encounters around the country:

-- U.S. paratroopers killed six attackers and wounded four others in a shootout Tuesday near the hospital run by the Jordanian government near Fallujah, the 82nd Airborne Division said.

-- In Abu Ghraib, 10 miles west of Baghdad, U.S. troops caught guerrillas who allegedly had just fired a mortar at coalition forces. The men got into a van and tried to escape but an Apache helicopter gunship fired at the vehicle, killing two and wounding three. Five rebels were captured.

-- Jumpy U.S. troops in Baghdad mistakenly fired on a car carrying Governing Council member Mohammed Bahr al-Uloun, wounding his driver.

-- Officials reported that two U.S. soldiers had been killed Tuesday in separate incidents involving improvised roadside land mines -- one near the town of Taji northwest of Baghdad, and the other in the capital.